Polymeric materials, such as polyamides, are used in many applications, such as in the manufacture of automobile parts and accessories, containers, consumer electronics devices, household appliances and other commercial items. More recently, polyamides reinforced with, for example, glass fibers, are being used in the construction of such articles. This reinforcement increases the rigidity, strength, and/or heat resistance of the polyamide, thereby providing a material that is more desirable in many applications.
It is often desired to coat articles made from such materials with one or more coatings to decorate and/or protect a surface thereof from degradation when exposed to, for example, atmospheric weathering conditions, such as sunlight, moisture, heat and cold. To achieve longer lasting and more durable parts, it is desirable that such coatings adhere well to the article surface.
In many cases, an adhesion-promoting layer is used on polymeric substrates, such as polyamide substrates, to improve the adhesion of subsequent applied coatings thereto. In many cases, these adhesion-promoting layers are formed from compositions that include chlorinated polyolefins and/or epoxy-amine chemistries. Unfortunately, the adhesion performance of such layers has not always been reliable, particularly when they have been applied to reinforced polyamide substrates of the type described above.
As a result, it would be desirable to provide coating compositions that are capable of providing coatings that adhere to polymeric substrates, including reinforced polyamide substrates, and which are suitable for the application of subsequent coatings.